Piptadenia retusa ( Jacquin 1760: 34 ) P.G. Ribeiro, Seigler & Ebinger (2020: 1)

Gomes, Aureliana Santos, Rodrigues, Erimágna De Morais, Moura, Débora Coelho, Melo, José Iranildo Miranda De, Ribeiro, Rayane De Tasso Moreira & Queiroz, Rubens Teixeira De, 2022, Fabaceae Lindl. in a Conservation Unit in the Semi-Arid Region of Paraíba, Brazil, Phytotaxa 555 (1), pp. 17-41 : 32-33

26. Piptadenia retusa ( Jacquin 1760: 34) P.G. Ribeiro, Seigler & Ebinger (2020: 1)

Trees, branches glabrous, aculeate. Nectary petiolar, sessile. Stipules caducous. Leaves bipinnate, paripinnate, 8– 24–foliolate, leaflets opposite, oblong, venation actinodromous, translucid punctuation absent. Inflorescence spike, axillary. Flowers sessile, actinomorphic, diplostemonous; calyx gamosepalous, sepals 5, corolla gamopetalous, tubular, yellow, petals 5; androecium dialystaminous, homodinamous, anthers longitudinal; ovary superior, sessile, pluriovulate. Fruit legume, sessile, linear, plane-corrugate, margin straight, epicarp glabrous, brown. Seeds obovate, plane, coat brown, hilum basal.

Examined material:— BRAZIL. Paraíba: Maturéia, Pico do Jabre , 900 m ele., 06 February 2020, fl., A . Gomes 3147 ( HACAM) .

Distribution and ecology: — Piptadenia retusa is restricted to the Caatinga phytogeographic domain, being found in the states of Alagoas, Bahia, Ceará, Paraíba, Pernambuco, Piauí, Rio Grande do Norte and Sergipe ( Cardoso & Queiroz 2007). In the study area, it was collected in the interior of the forest, at 900 m.

Phenology:— Registered with flower in February.

Taxonomic discussion:— Piptadenia retusa can be recognized, mainly, by the arboreous habit, branches with the presence of aculeous and inflorescences in axillary spike, differentiating itself from the other Mimosa species in the studied area by the presence of extrafloral nectary in the petiole and legume type fruit vs. extrafloral nectary absent and craspédio fruit.